An all-too-easy hiring mistake can sabotage your company's success

Scientific research suggests that managers tend to hire people who are similar to them, people who they'd want to befriend and hang out with.

On some level, that makes sense - after all, they'll be spending a lot of time together.

But in some circumstances this tendency can backfire and end up undermining the strength of the organization.

That's according to John Addison, CEO of Addison Leadership Group and former co-CEO of financial services marketing organization Primerica.

In his new book, "Real Leadership," Addison explains why Primerica's success can be partly attributed to the fact that he and his co-CEO had completely different backgrounds and skill sets (though they did enjoy spending time together).

In an interview with Business Insider, Addison said that hiring people who are too similar to you can hinder your success.

"Too many people want to have people around them who are just like them," he said. "But the reality is you want people whose skill sets complement your weaknesses, and then you're good at the other things."

Addison ran Primerica along with Rick Williams from 1999 to 2015, leading the company through a recession and through its separation from Citigroup and subsequent IPO. Before becoming CEOs, William had been Primerica's chief financial officer and Addison had been president.

The two couldn't be more different, Addison said.

For one, Addison grew up and was educated in Georgia; Williams grew up in New Jersey and received his MBA from Wharton.

Williams is a numbers guy and incredibly organized; Addison described himself as disorganized. While Williams would "rather get his teeth pulled than get in front of a group of people and speak, I've never met a microphone I don't like."

Addison believes their different management styles helped make them a powerful leadership team. "Each of us individually would probably have been a good CEO, with different ways of doing it," he said. "But together we were pretty hard to beat."

Addison isn't the only CEO to believe in the power of differences. Randi Zuckerberg, CEO of Zuckerberg Media, explained in an interview with Business Insider that one of the biggest mistakes entrepreneurs make is choosing a cofounder with the same skills.

It's important to partner with someone who has a different skill set, she said, so you don't step on each other's toes.

Ultimately, you and your business partner should have a single set of goals for the company, even in spite of your differences.

In the book, Addison writes that the differences between him and Williams were superficial. What mattered most was their shared values and vision for Primerica, and a shared commitment to strong leadership.